Valve



April 27, 1955 R. M. Nr-:sTER 3,180,610

v VALVE Filed April 5, 1962 Invezm" RaI/phMNes fer' Vused despite its well-'known shortcomings.

e y I,

UnitedStates Patent O 3,180,610 VALVE Ralph M. Nester, Newark, Del., assigner to Nester @e Faust Manufacturing Corp., a corporation oaf Delaware Filed Apr. 5, 1962, Ser. No. 185,4.33 7 Claims. (Cl. 251-150) This invention relates to a lnew valve structure. More particularly, it relates to a new device for metering out fluids which device is constructed of a syntheuc polymer Aof the fluorocarbon type. i

There are a great many applications in which small amounts of uids are required to be transferred trom one chamber to another. One example that will be used for purposes of discussion and description in this invention is the common bui-ette found in the chemical llloraory.

i e commonvalve or stopcoc as een lFor many years th one of these isthe necessity to grease the stopcock in order to make a seal and in order to provide for the turningof 4the stopcock. Despite the greased nature `of this particular valve,

sticking or :freezing of such stopcoeks is a common occu-r- A rence even during its use and'on standing out of use such freezing occurs. Further, a broken lor damaged stopcock generally leaves the bu-rette useless. 'Perhaps 'the most serious disadvantage of this type of -a valve lies in the fact that it is very diliicult lto regulate the passage of small drops from the burette to the container desired. The operator must deftly turn the stopcock in order to get `the right opening of the -bore exposed rto the iluid above 1t. This is a very difficult thing to do when the operator has to contend with a valve that is ditiicult to turn and a valve which does not yallow him to gauge how much is coming out until the iluid is actually coming out of the burette.

Accordingly, there has .been long felt a need for .improvement in valves for such llaboratory equipment such as burettes, separatory tunnels and the like.

An object of thisinvention is the provision ot a valve which presents la boring through which can be passed Q minute amounts of liquid upon the slight and easily ma-de ladjustment of a valve stem. Another purpose ofthis invention kisi to provide a valve which presents a mmimum of exposure of the mOVingpart forming the seal to the fluid which is to pass through the valve. A still further aim is the provision of a valve made of chemically inert materials. Another lobject is the providing of a closing and lopening means in the valve which is positively acting and which is substantially free of the possibility of jamming. These and other objectives will appear hereinafter. y

' The purposes of this invention are accomplished lby the provision of a valve which is made of a lluorocarbon resin such as polyttet-rauoroethylene). The valve comprises, in the main, two parts these being a plug or stopper made of the said fluorocarbon resin and having ai passageway through it from one end of it to another and in conduit relationship ,therewith -a movable part, which -may be vent iluid from passing through the valve, since the opening to the moveable part is closed bythe plug. Upon partially withdrawing the moveable member from the stopper by slight unthreading, the `operator can effect the ilow of liuid through the valve as desired. This invention will be further understood by reference to the description Mice tration and are not limitative, the figures being as follows:

FIGURE 1 is a side elevation, partly in section, showing the valve structure of this invention in the closed position;-

FIGURE 2 is an enlarged plan view of the stopper or the plug portion ot the valve of this invention;

FIGURE 3 is a sectional view taken on line 3-3 of FIGURE 2;

FIGURE 4, taken on line 4 4 of FIGURE 1, is a sectional elevation Iof several elements in an assembled relationship but detached from the structure illustrated in FIGURE 3;

FIGURE 5 is a further enlarged detail of the several .assembled elements of this invention comprising the valve structure and showing the valve in an open position; and

FIGURE 6 (a), (b) and (c) illustrate various tapered plugs that can be used. l

As shown in FIGURE l, the yburette 1 is sealed at its lower end with the stopper 2 in which is positioned the threaded valve stem 3. The plug 2 is constructed of a 4iluorocarbon resin, such as poly(tetraiiuoroethylene), but

it may tbe m-ade of a wide variety of materials including copolymers of tetraitluoroethylene with other monomers rsuch as monochlorotrilluoroethylene and hexa-fluoropropylene. However, in View of the chemical inertness and the stability of poly(tetrau-oroethylene) it is precterred by far as the material for-the stopper part of the valve of this invention. The moving, threaded element 3 is a piece of tubing made from such synthetic polymers as those named `above or from a large variety of metals including stainless steel, brass, copper, aluminum and the like. 'Usually yan inactive chemically'stable material is chosen such as poly(tetrafluoroethylene) or copper. This moving element has positioned around it sleeve 4 which is made of rubber, polyethylene or any similar device and which serves merely as a gripping means for which to turn the moving element 3. This sleeve 4 will slide up for down the moving element with ease.

As noted in FIGURE 1A and better in FIGURE 3 or FIIGURE 5, the plug 2 has conduit I5 cut down its side for a por-tion of its length from the topA extending toward the bottom and then cut inwardly at 6 to join the conduit 7 which extends from the bottom of the plug upwardly through the center part of ,the plug and a bit-beyond the fbottominost part of conduit S. The stopperZ that is shown in the figures is conical in construction and the conduit 5 can be seen in FIGURE 2 extending down the sides of the frustum. The upwardly extendingconduit 7 is shown in dotted lines in FIGURE 2. 'g The threads 8 on the inside of stopper 2 are vcarefully machined, and they mesh with a snug fit yet easily with the outside threads 9 of Valve stem or moving element 3. These threads, both the inside threads 8 vand the outer threads v9, need never be exposed to the iiuid passing through the valve, for the operator in varying the amount of the flow of the fluid from the closed position shown in FIGURE 1 need remove the moving element 3 no more than to the position of that element shown in FIGURE 5 which is a completely open position. Yet, the moving element 3 may be very easily completely removed from the stationary element 2,if desired. If desired moving element 3 and inner surfaces of the bore '7 may be smooth walled, the element 3 being slideably positioned in the conduit by ysnug fittings. Generally, however, the threaded modification is preferred for the adjustments are fine and precise and very easily made.

As will be noted in FIGURE 5, the internal, vertical bore 7 terminates in a frustum-shaped manner shown at 1t) in FIGURE 5. Similarly, the moving element 3 at its upper end terminates in a frustum-slaped manner shown at 1l in FIGURE 5. Upon screwing the element 3 cornpletely into the stopper 2 the surfaces or edges of element 3 at 11 enter snugly and tightly into the surfaces of the frustum-shaped end of tube 7 at 1t). A tight and positive seal results which. precludes the passage of any fluid from the burette when the valve stem 3 is in the closed position as shown in FIGURE 1. Further, the dove-tailed effect that is obtained prevents element 3 from cutting into the polymer in stopper 2 above element 3. When tube 3 terminates in a cylindrical cross-section such cutting can occur especially when tube 3 is made of a metal. Therefore, the frustum-shaped end or similar blunt endings are preferred.

The angles of the frustum shapes in stopper 2 can vary from to 185. As can be seen in FIGURE 6(a) the angle A ofthe plug can be very small with edge or surface 13 being within the container While in FIGURE 6(b) the angle A is very large, the edge or surface iftbeing within the container. In these instances the walls 15 of the container will curve inwardly in the freeze fitting of the plug as shown in FIGURE 6(0) This latter tigure shows a combination of straight and tapered Walls. Any of various forms may be used including completely straight or vertical Walls for thev plugs are very tightly held in place by the adjacent container walls. The exceptionally tight seals of this invention are attained by heating the container walls prior to inserting the plug or by cooling the plug before insertion. In the one instance the walls will contract firmly gripping the plug. In the other the plug will expand producing the tight seal. By such procedures a seal known as a freeze fit is'obtained. Further, the frusturn shape can be used in an inverted form. That is, the base may be at the top with a smaller end extending below the container 1. Of course, the bore 7 will then extend upwardly from the short basetoward the broader base. Still further, it will be appreciated that the stopper 2 may be octagonal, pentagonal or hexagonal in shape or in any shape'. that is desired to tit a given container. Thus, while the stopper 2 is shown in the shape of a frustum in the gures, it is to be understood that the valve of this invention is not limited to that shape. It will be further appreciated that the stopper irrespective of the number of sides it has can be straight walled or slanted outwardly or inwardly at suchv angles as those discussed above.

It will also be understood that the moveable element 3 is of any length desired. Similarly, the element maybe bent or curved and it may have attached to it a moveable piece of plastic 1,2 shown in FIGURE 4.

Whilethe invention has been disclosed herein in connection Vwith certain embodiments and certain structural and procedural details, it is cleas that changes, modications or equivalents can be used by those skilled in the art; accordingly, such changes within the principles of this` invention are intended to be included within the scope of the claims below.

I claim:

1. An article of manufacture being a plug and a valve Y for a container having an outlet which article comprises a piece of solid .tiuorocarbonfresin having a shape and dimensions on its outside surfaces to conform to the inside shape and dimensions of said outlet .aording thereby a plug for saidV outlet; inside said piece of resin three conduits, the iirst conduit being a threaded bore extending longitudinally from the bottom endof said plug almost Yto the opposite end, the second conduit being an unthreaded bore extending longitudinally from the top end to a point below the'upper end ofthe first conduit, but not aligned with thesaid lirst conduit and the third conduit being an Unthreaded bore extending transversely and vconnecting the rst and the second conduits; and positioned in said rst conduit a movable, hollow element havingfexternal threads meshable with said threads of said rst conduitand being, depending upon its position, in passageway relationship with said rst, second and third conduits and having a length longer .than the length of said first conduit. y

2. An article in accordance with claim 1 inwhich said first conduit terminates at itsupper, innermost end in an end section that has a `shape and dimensions conforming to the outer shape and dimensions of the inner end of said movable element positioned within it.

3. An article -in accordance'with vclaim l in which saidfplug is made of poly(tetraiiuoroethylene).

4. An' article in accordance with'claim l which has been frozen into place in said outlet.

5. A precision metering device comprising a stationary element constructed of a iiuoroca'rbon resin and adapted to be fitted into an open end of a burette-lilce tubular container, said stationary element containing an [1 -shaped channel which extends partially into said element and which opens into a second channel within said stationary element; vertically disposed relative tothe said base of the L-shaped channel the'said second channel which bears internal threads and has at its innermost end a frustumliketerminus; and inY combination with said second channeland extending beyond said stationary element, a movable tubular element bearing external threads meshable with said internal threads and co-acting with the stationary element ,to seat snugiy'in said terminus and seal the said: L.'shaped channel.

6. AA device in accordancefwith claim 5 in which said stationary element .is made up of poly(tetraliuoroethyl ene).

References -Cited by the Exauniunnr'Y UNITED `STATES PATENTS M. CARY NELSON, Prfmmy Examiner. 

1. AN ARTICLE OF MANUFACTURE BEING A PLUG AND A VALVE FOR A CONTAINER HAVING AN OUTLET WHICH ARTICLE COMPRISES A PIECE OF SOLID FLUORCARBON RESIN HAVING A SHAPE AND DIMENSIONS ON ITS OUTSIDE SURFACES TO CONFORM TO THE INSIDE SHAPE AND DIMENSIONS OF SAID OUTLET AFFORDING THERE BY A PLUG FOR SAID OUTLET; INSIDE SAID PIECE OF RESIN THREE CONDUITS, THE FIRST CONDUIT BEING A THREADED BORE EXTENDING LONGITUDIALLY FROM THE BOTTOM END OF SAID PLUG ALMOST TO THE OPPOSITE END, THE SECOND CONDUIT BEING AN UNTHREADED BORE EXTENDING LONGITUDINALLY FROM THE TOP END TO A POINT BELOW THE UPPER END OF THE FIRST CONDUIT, BUT NOT ALIGNED WITH THE SAID FIRST CONDUIT AND THE THIRD CONDUIT BEING AN UNTHREADED BORE EXTENDING TRANSVERSELY AND CONNECTING THE FIRST AND SECOND CONDUITS; AND POSITIONED IN SAID FIRST CONDUIT A MOVABLE, HOLLOW ELEMENT HAVING EXTERNAL THREADS MESHABLE WITH SAID THREADS OF SAID FIRST CONDUIT AND BEING, DEPENDING UPON ITS POSITION, IN PASSAGEWAY RELATIONSHIP WITH SAID FIRST, SECOND AND THIRD CONDUITS AND HAVING A LENGTH LONGER THAN THE LENGTH OF SAID FIRST CONDUIT. 